Audio breakout box for MacBook Pro

[Billy] wanted to use the audio connector on his MacBook Pro for input and output at the same time. He knew it could be done because Apple sells headphones with built-in microphones that work with the computer. He set out to build a breakout box so that he could connect the components of his choice to the single port. Using a scart-RCA adaptor box he scrapped the scart plug and wired the RCA jacks to the Apple headphone wires. He can now patch the pickup of his guitar to the mic connector, send it through the MacBook, and run the output back to his guitar amp.

this would only work with this macbook pro or other apple devices that use a single audio port. apple have a habit of deviating from the standard. the pins used in this type of connector are different from the pins in the apple connectors. the tip of the jack usually handles audio in, whereas on this one its the sleeve connection.

This article is just a filler for an obviously slow day, this is more common knowledge then anything, might as well show people how to tape and glue stuff together instead of calling them hacks, if the mac had a special chip like the ipod first party usb cord to do this, and he bypassed it it would be more considered a hack, but cutting cables and throwing them in a box, come on

If you guys would read the link, you’d know that it’s “for MacBook Pro” because the new MacBook Pros collapse the separate input and output mic jacks into a single jack that changes function by an OS setting. His hack emulates the functionality of Apple’s proprietary connector that allows simultaneous recording and playback.

@Icarus- The builder said that this wasn’t the ideal hack, but use what was at hand. Also mentioned a series of connectors(I assume various adapters) where used to interconnect everything. Given the anonymous internet critics, it’s a wonder people still document, and share their projects.

anonymous critics are best ignored. Constructive critics are given time of day, while congrats are well received.

at least this is my rule.

and as for anything that prevents more accessories with apple’s “proprietary so you have to buy it from us” crap in it the better I say. I don’t care how ugly it is. I’d rather have ugly and functional than expensive and warranty voided if you’re ever around a smoker.

While Apple should certainly provide an audio line in, this seems a nice, simple solution to the problem. It’s not the most spectacular thing you’ll see today, but I could imagine quite a few people using it as a workaround.

Anyways, why would you want to run your guitar to the laptop first and then to the amp? Assuming you’re trying to record the guitar on the laptop, the sound you hear out of the amp wouldn’t be what you’re recording.

hahah :D got my laughs for the day. You only encounter problems like this with MAC. This is my first laptop i ever saw that doesnt have separate audio input and output… this is just stupid or then i must have not seen enough laptops :P

@stehphen gentle:
Macbooks do have excellent audio outputs, I saw test with almost 100db S/N ratio and very low THD. Inputs performed very well, too. These tests were commited by german computer magazine c’t some while back, but I think they should still be valid.

I didn’t even notice that the 13.3″ Pros only come with a single audio port. The 15″ and 17″ both come with dedicated audio out and in. The older white ones came with two also. Guess that’s just Apple’s way of pushing people to buy the more expensive models…

And as a bit of constructive criticism to the modder, it would be much wiser to plug the guitar directly into the amp, and then run an output from the amp into the breakout box. You’ll get much better sound quality and reduce the slight risk there may be of frying the audio jack. Nice workaround though.

Oh, and one more thought: couldn’t you just wire an audio in port to the microphone connection (if you don’t use it often) on the logic board and mount a new jack in the case? It’d require more hacking, but it’d probably work just as well and it’d be more Hackaday-ish material.

Or a USB midi DAW breakout box?
There are similar usb audio only bypassing the suspect quality macbookpro audio inputs altogether.
Good on him for building his own solution though. We all start somewhere to the negative nancies on here. We also all reach that cost-effective point of hacking too, though, lol and that a $5 USB dongle can sometimes be worth it. Also to the builder, turn off your synth chip to kill some background hiss. You will notice a lot of things when you hook up to real studio amps for mixing later ;) Leave a few seconds of base level so you can sample for noise reduction later on ;) Have fun with your in home studio :)

It’s a workaround to a problem I’ve been bashing my head against for a while. There’s a lot of macs in the desktop publishing trade, and Apple has been throwing non standard 3.5 mm audio jacks (or no audio jacks, or an almost 3.5 mm jack for proprietary speakers that would fry anything else you plugged in) in to the mix semi-randomly since about 2002. A lot of people using those macs have started to use VoIP or recording tools for various reasons, and one by one they reach to the back of their machines only to find that a 30 year standard vanished when nobody was looking.

Apple does the same thing with video, too. They swapped out the full size DVI port with a miniature proprietary one, and every year they swap a pin and move a plastic tab around so you need to buy a $30 dongle for your $1500 machine. Anyone remember the “there’s no step three!” advertising push that came with the G3 iMacs in the late 90’s? Having a half dozen dongles, adapters, and breakouts sticking out the sides of the box is one hell of a backslide.

Being able to thumb your nose at even one of those iDapters is a good thing.

Just an update on this, this is mono only input while the jack is selected as audio out in System Preferences, as it uses the fourth conductor on the jack. Haven’t tested it, but this could also mean it provides for three channel input if your software supports it.